Factors Affecting Growth and Toxin Production by Clostridium Botulinum Type E on Irradiated (0.3 Mrad) Chicken Skins

ABSTRACT

A model system (chicken skins with chicken exudate) was used to determine if Clostridium botulinum type E (Beluga) spores, stressed by low dose irradiation, would develop and produce toxin at abuse temperatures of 10 and 30°C in the absence of characteristic spoilage. Unstressed spores germinated, multiplied, and produced toxin on vacuum-packed chicken skins, stored at either 30 or 10°C. Cell numbers increased faster and toxin was evident sooner at 30°C than at 10°C. At 30°C, growth occurred and toxin was produced more slowly when samples were incubated aerobically than anaerobically. When samples were incubated aerobically at 10°C, no toxin was detected within a test period of 14 days. An irradiation dose of 0.3 Mrad at 5°C reduced a spore population on vacuum-sealed chicken skins by about 90%. The surviving population produced toxin at 30°C under either aerobic or anaerobic conditions, at 10°C no toxin was detected even on skins incubated anaerobically. Under the worst conditions (30°C, vacuum packed) toxin was not detected prior to characteristic spoilage caused by the natural flora surviving 0.3 Mrad.